From 2d676c961ebac28e616eae9ff95ad55eebb49172 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sun, 24 Jun 2001 04:07:44 +0000
Subject: [PATCH] New file due to the Intervals.h splitup
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Analysis/IntervalPartition.cpp | 181 +++++++++++++++++++++++++++++
1 file changed, 181 insertions(+)
create mode 100644 lib/Analysis/IntervalPartition.cpp
diff --git a/lib/Analysis/IntervalPartition.cpp b/lib/Analysis/IntervalPartition.cpp
new file mode 100644
index 00000000000..84104777841
--- /dev/null
+++ b/lib/Analysis/IntervalPartition.cpp
@@ -0,0 +1,181 @@
+//===- IntervalPartition.cpp - Interval Partition module code ----*- C++ -*--=//
+//
+// This file contains the definition of the cfg::IntervalPartition class, which
+// calculates and represent the interval partition of a method.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/IntervalIterator.h"
+
+using namespace cfg;
+
+//===----------------------------------------------------------------------===//
+// IntervalPartition Implementation
+//===----------------------------------------------------------------------===//
+
+template <class T> static inline void deleter(T *Ptr) { delete Ptr; }
+
+// Destructor - Free memory
+IntervalPartition::~IntervalPartition() {
+ for_each(begin(), end(), deleter<cfg::Interval>);
+}
+
+// addNodeToInterval - This method exists to assist the generic ProcessNode
+// with the task of adding a node to the new interval, depending on the
+// type of the source node. In the case of a CFG source graph (BasicBlock
+// case), the BasicBlock itself is added to the interval.
+//
+inline void IntervalPartition::addNodeToInterval(Interval *Int, BasicBlock *BB){
+ Int->Nodes.push_back(BB);
+ IntervalMap.insert(make_pair(BB, Int));
+}
+
+// addNodeToInterval - This method exists to assist the generic ProcessNode
+// with the task of adding a node to the new interval, depending on the
+// type of the source node. In the case of a CFG source graph (BasicBlock
+// case), the BasicBlock itself is added to the interval. In the case of
+// an IntervalPartition source graph (Interval case), all of the member
+// BasicBlocks are added to the interval.
+//
+inline void IntervalPartition::addNodeToInterval(Interval *Int, Interval *I) {
+ // Add all of the nodes in I as new nodes in Int.
+ copy(I->Nodes.begin(), I->Nodes.end(), back_inserter(Int->Nodes));
+
+ // Add mappings for all of the basic blocks in I to the IntervalPartition
+ for (Interval::node_iterator It = I->Nodes.begin(), End = I->Nodes.end();
+ It != End; ++It)
+ IntervalMap.insert(make_pair(*It, Int));
+}
+
+
+// ProcessNode - This method is called by ProcessInterval to add nodes to the
+// interval being constructed, and it is also called recursively as it walks
+// the source graph. A node is added to the current interval only if all of
+// its predecessors are already in the graph. This also takes care of keeping
+// the successor set of an interval up to date.
+//
+// This method is templated because it may operate on two different source
+// graphs: a basic block graph, or a preexisting interval graph.
+//
+template<class NodeTy, class OrigContainer>
+void IntervalPartition::ProcessNode(Interval *Int,
+ NodeTy *Node, OrigContainer *OC) {
+ assert(Int && "Null interval == bad!");
+ assert(Node && "Null Node == bad!");
+
+ BasicBlock *NodeHeader = getNodeHeader(Node);
+ Interval *CurInt = getBlockInterval(NodeHeader);
+ if (CurInt == Int) { // Already in this interval...
+ return;
+ } else if (CurInt != 0) { // In another interval, add as successor
+ if (!Int->isSuccessor(NodeHeader)) // Add only if not already in set
+ Int->Successors.push_back(NodeHeader);
+ } else { // Otherwise, not in interval yet
+ for (typename NodeTy::pred_iterator I = pred_begin(Node),
+ E = pred_end(Node); I != E; ++I) {
+ if (!Int->contains(*I)) { // If pred not in interval, we can't be
+ if (!Int->isSuccessor(NodeHeader)) // Add only if not already in set
+ Int->Successors.push_back(NodeHeader);
+ return; // See you later
+ }
+ }
+
+ // If we get here, then all of the predecessors of BB are in the interval
+ // already. In this case, we must add BB to the interval!
+ addNodeToInterval(Int, Node);
+
+ if (Int->isSuccessor(NodeHeader)) {
+ // If we were in the successor list from before... remove from succ list
+ Int->Successors.erase(remove(Int->Successors.begin(),
+ Int->Successors.end(), NodeHeader),
+ Int->Successors.end());
+ }
+
+ // Now that we have discovered that Node is in the interval, perhaps some of
+ // its successors are as well?
+ for (typename NodeTy::succ_iterator It = succ_begin(Node),
+ End = succ_end(Node); It != End; ++It)
+ ProcessNode(Int, getSourceGraphNode(OC, *It), OC);
+ }
+}
+
+
+// ProcessInterval - This method is used during the construction of the
+// interval graph. It walks through the source graph, recursively creating
+// an interval per invokation until the entire graph is covered. This uses
+// the ProcessNode method to add all of the nodes to the interval.
+//
+// This method is templated because it may operate on two different source
+// graphs: a basic block graph, or a preexisting interval graph.
+//
+template<class NodeTy, class OrigContainer>
+void IntervalPartition::ProcessInterval(NodeTy *Node, OrigContainer *OC) {
+ BasicBlock *Header = getNodeHeader(Node);
+ if (getBlockInterval(Header)) return; // Interval already constructed?
+
+ // Create a new interval and add the interval to our current set
+ Interval *Int = new Interval(Header);
+ IntervalList.push_back(Int);
+ IntervalMap.insert(make_pair(Header, Int));
+
+ // Check all of our successors to see if they are in the interval...
+ for (typename NodeTy::succ_iterator I = succ_begin(Node), E = succ_end(Node);
+ I != E; ++I)
+ ProcessNode(Int, getSourceGraphNode(OC, *I), OC);
+
+ // Build all of the successor intervals of this interval now...
+ for(Interval::succ_iterator I = Int->Successors.begin(),
+ E = Int->Successors.end(); I != E; ++I) {
+ ProcessInterval(getSourceGraphNode(OC, *I), OC);
+ }
+}
+
+
+
+// updatePredecessors - Interval generation only sets the successor fields of
+// the interval data structures. After interval generation is complete,
+// run through all of the intervals and propogate successor info as
+// predecessor info.
+//
+void IntervalPartition::updatePredecessors(cfg::Interval *Int) {
+ BasicBlock *Header = Int->getHeaderNode();
+ for (Interval::succ_iterator I = Int->Successors.begin(),
+ E = Int->Successors.end(); I != E; ++I)
+ getBlockInterval(*I)->Predecessors.push_back(Header);
+}
+
+
+
+// IntervalPartition ctor - Build the first level interval partition for the
+// specified method...
+//
+IntervalPartition::IntervalPartition(Method *M) {
+ BasicBlock *MethodStart = M->getBasicBlocks().front();
+ assert(MethodStart && "Cannot operate on prototypes!");
+
+ ProcessInterval(MethodStart, M);
+ RootInterval = getBlockInterval(MethodStart);
+
+ // Now that we know all of the successor information, propogate this to the
+ // predecessors for each block...
+ for(iterator I = begin(), E = end(); I != E; ++I)
+ updatePredecessors(*I);
+}
+
+
+// IntervalPartition ctor - Build a reduced interval partition from an
+// existing interval graph. This takes an additional boolean parameter to
+// distinguish it from a copy constructor. Always pass in false for now.
+//
+IntervalPartition::IntervalPartition(IntervalPartition &I, bool) {
+ Interval *MethodStart = I.getRootInterval();
+ assert(MethodStart && "Cannot operate on empty IntervalPartitions!");
+
+ ProcessInterval(MethodStart, &I);
+ RootInterval = getBlockInterval(*MethodStart->Nodes.begin());
+
+ // Now that we know all of the successor information, propogate this to the
+ // predecessors for each block...
+ for(iterator I = begin(), E = end(); I != E; ++I)
+ updatePredecessors(*I);
+}